1. Field of the Invention
The present invention generally relates to a method for manufacturing a semiconductor device, and more specifically, to a method for manufacturing a semiconductor device that includes depositing a flowable oxide (FOX) dielectric material over a semiconductor substrate, and exposing a local active region to grow an active region by a Silicon Epitaxial Growth (SEG) method to prevent generation of a void when a device isolation structure is formed and to prevent stress between the semiconductor substrate and the FOX dielectric material.
2. Brief Description of Related Technology
Due to high-integration of semiconductor devices, a critical dimension CD of a gate becomes smaller, and a channel length is reduced, which causes a short channel effect (SCE) to degrade an electric characteristic of a field effect transistor (FET).
To prevent the SCE, a Multi-channel Field Effect Transistor (McFET) having a multi channel gate, such as a recessed gate, has been used. The recessed gate is obtained by etching a given depth of an active region of a semiconductor substrate to increase a channel length.
The high-integration of semiconductor devices reduces a process margin for forming an active region and a device isolation structure.
Because a gap between device isolation structures that define an active region becomes smaller, a dielectric material which is a flowable oxide (FOX) for filling a trench of a device isolation structure formed by a Shallow Trench Isolation (STI) method is used in a current single High Density Plasma (HDP), and a Spin On Dielectric (SOD), a HDP Bi layer or other materials are filled.
A trench for forming a device isolation structure is narrow to generate a void when the trench is filled with a dielectric material. A transistor characteristic is degraded by a stress of the dielectric material.